EARTH CITY, Mo. -- It’s been almost a decade since the Rams have had anything even remotely resembling a competition for their starting running back position.

Since the Rams used the 24th overall pick in the 2004 NFL draft on him, Steven Jackson’s name might as well have been etched in stone at the top of the depth chart. From that time, no running back in the NFL even came close to handling Jackson’s workload.

With Jackson now making his NFL home in Atlanta, the Rams find themselves entering their first season post-Jackson in search of a new starter at running back.

“I think Daryl comes back as our starter because he played significantly more last year than anybody,” Fisher said. “And so Isaiah is working himself up and competing with Daryl. And you’ve got the rest of the guys that are just going to battle it out, and we haven’t ruled anybody out from that matter. But we’re going to try to get as many carries as we can.”

So while Richardson “comes back as the starter,” there seems to be plenty of wiggle room as the Rams head into the preseason opener in Cleveland tomorrow night. Beyond that, calling Richardson the starter now could also be a matter of semantics, because Pead’s one-game suspension for violating the league’s substance abuse policy will keep him out of the opener against Arizona.

Nearly two weeks into this year’s training camp, Richardson and Pead have spent most of the time in practice splitting repetitions with the first team. Richardson got many of the looks in the opening days before the Rams put the pads on, but since then he and Pead have been taking turns on a fairly consistent basis.

Neither Pead nor Richardson believes the job is anything but up for grabs as the exhibition schedule kicks off.

“I can’t call it right now, I can’t really tell,” Pead said. “All I can focus on is the next play and trying not to make a mistake on it or fixing it if I’ve currently made a mistake on it. That’s really the mindset that all of us as vets have taken, not really paying attention to how things are going to play out, but letting them play out.”

Ultimately, no matter who wins the starting job, it’s highly unlikely the Rams will lean on one back as they did Jackson.

From 2004 to 2012, Jackson’s 2,396 carries were the most in the league. Thomas Jones’ 2,179 attempts rank second.

In St. Louis, the discrepancy is even greater. Marshall Faulk, who played with Jackson in Jackson’s rookie season, had the next highest total after Jackson’s with 260.

All told, the Rams had 59 players carry the ball during Jackson’s tenure. In that time, the Rams tallied 3,665 carries; meaning Jackson’s total was good for 65.3 percent of the team’s total carries in his nine years with the team.

Richardson actually sits fourth on that list after one season in the league, carrying 98 times for 475 yards as a rookie in 2012. Richardson is the fastest of the group, and showed a penchant for breaking the long run with 11 carries of 10-plus yards.

That speed would seem to make Richardson an ideal complementary back, but he says he made it a point in the offseason to add strength so he could be better between the tackles and be more stout picking up the blitz.

“I want to be the guy at the beginning and at the end,” Richardson said. “I am out here working every day, on my hands especially. Pass protection is a must. You have got to protect [quarterback] Sam [Bradford]. That’s the main focus on what will go on the field.”

Those things should help his cause, but Richardson is well aware that ball security is another issue he has to work on during the rest of the preseason. As a rookie, he coughed up three fumbles, two of which were lost.

“You have got to hold on to that ball,” Richardson said. “Holding on to the ball can be the thing that will make you or break you.”

Pead is the most likely to push Richardson and potentially claim the job before the regular season begins. After the Rams used a second-round pick (No. 50 overall) on him in the 2012 draft, Pead fell behind early in last year’s camp and Richardson claimed the backup job early on.

From there, Pead didn’t get many opportunities as he carried 10 times for 54 yards. Like Richardson, Pead brings a speedy running style, but is probably a bit more elusive in the open field.

By his own admission, Pead would like to be the type of multi-purpose player who touches the ball 30 times a game via the run, the catch and as a returner, but for now, his goal is to improve in all areas so he can win the starting job.

“I think every snap counts,” Pead said. “Every blitz picked up, every dropped ball, every missed cut, every missed assignment. We are all out here looking not to make mistakes. You pray for a perfect practice every day, it just doesn’t happen. But that’s what you have coaches for, and that’s what you come out every day for, and that’s what competition is for. It forces you to be on high alert and perform.”

Pead and Richardson will get plenty of opportunities to create separation through the preseason, but other backs such as rookie Zac Stacy, Terrance Ganaway and maybe even Benjamin Cunningham will get their chances. How soon those other backs get their chance remains to be seen as Stacy hasn’t done much in practice the past two days, and Ganaway appeared to tweak something on a run late in Tuesday’s workout.

“You just have to sit down and give it some thought,” Fisher said. “Out of fairness to them, you want them all to have an opportunity to run behind the first line, because that’s a fair evaluation -- and run against good opponents. So, we’re going to have to work that out the best we can.”